1 /* NaNs and Infinity in floating-point numbers. 2 Copyright (C) 2015-2019 Free Software Foundation, Inc. 3 4 This file was written by Daiki Ueno <ueno@gnu.org>, 2015. 5 6 This program is free software: you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 18 19 /* Replacement 'trionan.c', using Gnulib functions. */ 20 21 #include "config.h" 22 #include <float.h> 23 #include <math.h> 24 25 /* Copied from gnulib/tests/infinity.h. */ 26 27 /* Infinityd () returns a 'double' +Infinity. */ 28 29 /* The Microsoft MSVC 9 compiler chokes on the expression 1.0 / 0.0. */ 30 #if defined _MSC_VER 31 static double Infinityd()32Infinityd () 33 { 34 static double zero = 0.0; 35 return 1.0 / zero; 36 } 37 #else 38 # define Infinityd() (1.0 / 0.0) 39 #endif 40 41 /* Copied from gnulib/tests/nan.h. */ 42 43 /* NaNd () returns a 'double' not-a-number. */ 44 45 /* The Compaq (ex-DEC) C 6.4 compiler and the Microsoft MSVC 9 compiler choke 46 on the expression 0.0 / 0.0. */ 47 #if defined __DECC || defined _MSC_VER 48 static double NaNd()49NaNd () 50 { 51 static double zero = 0.0; 52 return zero / zero; 53 } 54 #else 55 # define NaNd() (0.0 / 0.0) 56 #endif 57 58 /* Copied from gnulib/tests/minus-zero.h. */ 59 60 /* minus_zerod represents the value -0.0. */ 61 62 /* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0. 63 ICC 10.0 has a bug when optimizing the expression -zero. 64 The expression -DBL_MIN * DBL_MIN does not work when cross-compiling 65 to PowerPC on Mac OS X 10.5. */ 66 #if defined __hpux || defined __sgi || defined __ICC 67 static double compute_minus_zerod(void)68compute_minus_zerod (void) 69 { 70 return -DBL_MIN * DBL_MIN; 71 } 72 # define minus_zerod compute_minus_zerod () 73 #else 74 static double minus_zerod = -0.0; 75 #endif 76 77 #undef INFINITY 78 #undef NAN 79 80 #define INFINITY Infinityd() 81 #define NAN NaNd() 82 83 #define trio_pinf() INFINITY 84 #define trio_ninf() -INFINITY 85 #define trio_nan() NAN 86 #define trio_nzero() minus_zerod 87 88 #define trio_isnan(x) isnan(x) 89 #define trio_isinf(x) isinf(x) 90 #define trio_signbit(x) signbit(x) 91